From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-next, PATCH 2/2] net: socionext: remove mmio reads on Tx Date: Sat, 15 Dec 2018 13:15:45 -0800 (PST) Message-ID: <20181215.131545.1617213294915409370.davem@davemloft.net> References: <1544777941-24083-1-git-send-email-ilias.apalodimas@linaro.org> <1544777941-24083-2-git-send-email-ilias.apalodimas@linaro.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, jaswinder.singh@linaro.org, ard.biesheuvel@linaro.org, masami.hiramatsu@linaro.org, masahisa.kojima@linaro.org To: ilias.apalodimas@linaro.org Return-path: Received: from shards.monkeyblade.net ([23.128.96.9]:55790 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727206AbeLOVPp (ORCPT ); Sat, 15 Dec 2018 16:15:45 -0500 In-Reply-To: <1544777941-24083-2-git-send-email-ilias.apalodimas@linaro.org> Sender: netdev-owner@vger.kernel.org List-ID: From: Ilias Apalodimas Date: Fri, 14 Dec 2018 10:59:01 +0200 > Currently the driver issues 2 mmio reads to figure out the number of > transmitted packets and clean them. We can get rid of the expensive > reads since BIT 31 of the Tx descriptor can be used for that. > We can also remove the budget counting of Tx completions since all of > the descriptors are not deliberately processed. > > Performance numbers using pktgen are: > size pre-patch(pps) post-patch(pps) > 64 362483 427916 > 128 358315 411686 > 256 352725 389683 > 512 215675 216464 > 1024 113812 114442 > > Signed-off-by: Ilias Apalodimas Applied.